STUDIES ON SULFATIDES BY QUADRUPOLE ION-TRAP MASS SPECTRMETRY WITH ELECTROSPRAY

四极杆离子阱电喷雾质谱研究硫醚

• 批准号: 7355210
• 负责人: FONG-FU HSU
• 金额: $ 0.85万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2007-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7355210
• 关键词: STUDIES; SULFATIDES; QUADRUPOLE; ION; TRAP

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The structural characterization of sulfatides by collisional-activated dissoctiation (CAD) quadrupole ion-trap tandem mass spectrometric methods with electrospray ionization is described. When subjected to CAD in the negative-ion mode, the [M - H](-) ions of sulfatides yield abundant structurally informative ions that permit unequivocal assisgmensts of the long-chain base, and fatty acid constituent including the location of double bond. The identification of the position of the double bond on the fatty acyl substitute is based on the observation of the series of the ions arising from classical charge-remote fragmentation processes similar to those observied by high-energy CAD and by tandem quadrupole mass spectrometry. An unusual internal galactose residue due to a rearrangement process was also observed. The [M - H](-) ions of sulfatides also dissociates to a ceramide anion, which undergoes consecutive fragmentation porcesses to yield ions informative for identification of teh ceramide moiety and premits distinction the sulfatide with a sphingosine subclass from that with a sphinganine long-chain base subclass. The MS(2)-spectra of the sulfatide subclass with a spingosine LCB and a alpha-hydroxy fatty acyl substituent (d18:1/hFA-sulfatide) are featured by the prominent ion sets of m/z568, 550, 540 and 522, originated from a primary cleavage of the fatty acyl CO CH(OH) bond, and are readily differentiable from those arising from the non-hydroxy sulfatide subclass (d18:1/nFA-sulfatide), in which the ion sets are low abundance. The fragmentation pathways of sulfatides under low-energy CAD are proposed. The pathways are supported by the MS- and MS-spectra of various compounds, and of their H-D exchanged analogs.

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。介绍了电喷雾电离碰撞活化解离（CAD）四极离子阱串联质谱方法对硫醚的结构表征。当在负离子模式下进行CAD时，硫脂脂的[M - H]（-）离子产生大量的结构信息离子，可以明确地确定长链碱基和脂肪酸成分，包括双键的位置。鉴定脂肪酸酰基替代物上双键的位置是基于对经典电荷远程破碎过程中产生的一系列离子的观察，类似于高能CAD和串联四极杆质谱法所观察到的。由于重排过程，还观察到不寻常的内部半乳糖残留物。磺胺脂的[M - H]（-）离子也解离成神经酰胺阴离子，神经酰胺阴离子经历连续的分裂过程，产生用于神经酰胺部分识别的离子，并使具有鞘氨醇亚类和具有鞘氨醇长链碱亚类的硫胺脂区分。具有自旋糖基LCB和α -羟基脂肪酸基取代基（d18:1/hFA-sulfatide）的硫脂酰亚类（MS(2)-光谱）的特征是明显的离子组m/z568、550、540和522，这些离子组源于脂肪酰基CO - CH（OH）键的初级裂解，并且很容易与非羟基硫脂酰亚类（d18:1/nFA-sulfatide）的离子组区分，后者的离子组丰度较低。提出了低能CAD作用下硫脂质的裂解途径。这些途径得到了各种化合物及其H-D交换类似物的质谱和质谱的支持。